Questions about Open-Drain devices and protocols. Open-Drain connections have two states, Open/Floating, or Drain to ground. Typically require Pullup resistors.

Questions about Open-Drain devices and protocols. Open-Drain connections have two states, Open/Floating, or Drain to ground. Typically require Pullup resistors.

Open-Drain devices typically have N-Channel Mosfets, and are common in LED Drivers, and is an essential part of protocols like I2C. The Drain in Open-Drain refers to the Drain of the Mosfet used.

They are similar to Open-Collector Devices, which use NPN Transistors instead of N-Channel Mosfets.

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